Fix regressions in configuration properties

- Restore old default password for billing service

- Fix property chaining for dcache.net.inetaddr.lifetime

- Restore original time unit for httpd properties (otherwise
  the old properties cannot be used as their meaning would
  change).

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Albert Rossi <arossi@fnal.gov>
Patch: http://rb.dcache.org/r/5861/